Adjustable counterbalance



1941- R. E. SCHULLER ,095

ADJUSTABLE COUNTERBALANCE Filed Nov. 12, 1938 2 Sheets-Sheet 1 YQRESCHULLER Jan. 7, 1941. R E SCHULLER v 2,228,095

' ADJUSTABLE COUNTERBALANCE Filed Nov. 12, 1958 Z SheetS-Sheet 2 jRESCHULLER. 5 mgg elik Patented Jan. 7, 1941 UNITE STATES ATENT OFFICELufkin Foundry & County, Tex.

Machine Company, Lufkin Application November 12, 1938, Serial No.239,955

3 Claims.

The invention relates to an improvement in adjustable ccunterbalances ofthe type which are applied to well pumping units.

In the pumping of a well various problems in counterbalahci-ng areencountered due to the variation in the depth of a well, the specificgravity of the fluid being pumped, the crookedness of the hole, and theweight of the equipment which must be operated. When all of these itcircumstances-are taken into consideration it is desirable to have acounterbalance weight which is readily adjustable to a very accuratedegree so that there will be the least power consumption.

With the foregoing in mind, it is one of the objects of the invention toprovide a universally adjustable counterbalance weight device forpumping units.

Anotherobject of the invention is to provide a counterbalance devicewhich can/be adjusted with minute accuracy in order to exactlycounterbalance the weight in the well.

Another object of the invention is 'to provide a circularhub member uponwhich a pair of 4) weight members are .circumferentially adjustable toany position independently of each other.

Another object of the invention is toprovide a counterbalancing devicein which a pair of counterbalance weights may be adjusted to lead,

coincide or lag with respect to each other or with respect to the wristpin openings.

Another object of the invention is to provide a counterbalance weightsupport member having a pair of parallel trackways thereon for the ad-,35 justment of counterbalance weights.

It is also an object to provide a cranking unit with an adjustablecounterbalance on the back .side crank so that one or more wellsmay becounterbalanced.

Another object of the invention is to provide a support member which maybe affixed to a crank shaft and haveadjustable counterbalance weightmembers affixed thereto.

Other and further objects of the invention will be readily apparent whenthe following description is considered in connection with theaccompanying drawings wherein:

Fig. 1 shows a side elevation of the counterbalance support and thecounterbalance weights afiixed thereto.

Fig. 2 is a section taken on the line 2-2 of Fig. 1.

Fig. 3 is a diagrammatic view showing the general assembly of the devicein operation.

Fig. 4 shows a view which is partly a top plan View and partly sectionon the line 4-4 of Fig. 6, and shows a modification of the inventionwhere the present crank has been applied to a cranking unit as a backside crank so that a plurality of wells may be pumped by the back sidecrank while at least-one well is being cranked by the front crank.

Fig. 5 is an elevation on the line 5-5 of Fig. 4 looking toward thefront crank.

Fig. 6 is a side elevation looking at Fig. 4 from the opposite side andillustrating the back side crank.

In Fig. 3 the walking beam 2 rocks on the center iron 3, which issupported on the Sampson post 4. The pitman rod 5 is connected to thewrist pin 6 in the wrist pin opening 1 in the crank arm portion 8 of thesupport or crank disc 9.

The pumping unit which is in the nature of a gear reduction box ID has ashaft H projecting laterally therefrom and the support member 9 is fixedto this shaft by the keys [2 which lit in the keyways iii. A throughbolt I4 passing through the lugs l5 and l 5 clamps the keys about theshaft H. In this manner the support member 9 is firmly fixed forrotation with the shaft l l.

A plurality of wrist pin openings 1 have been provided so as to vary thelength of the stroke of the pump.

Fig. 2 shows a sectional view of the support member I9 and illustratesthe arrangement of the rim 2t thereof, which as will be observed is ofconsiderable width so as to provide a pair of spaced trackways 2! and22. These trackways are identical and are slightly indented to providethe opposite shoulders 23 and 24. These shoulders extend entirely aroundthe periphery of the support member.

Eachof the trackways 2i and 22 are arranged to adjustably support acounterweight such as the weight 3.6. This weight is of particularconstruction, in that it has the body portion 3|, which has a shank 32connected therewith. This shank is provided with a substantiallysemi-circular base 33 which is of a configuration to fit the trackway22. The ears 34 at each side of the shank 32 are arranged to receive thebolts 35 and the nuts 35 thereon. In order that the weight 30 may beclamped on the trackway 22 a strap or band portion 31 is placed on theopposite half of the trackway 22. This band 31 is substantiallysemi-circular and has the ear-like portions 38 thereon, which haveopenings therethrough to receiVe the bolt 35. The head 39 of the bolt 35bears against this ear 38 so that when the nut 36 is drawn up the strap31 and the Weight 30 will be clamped rigidly to the support member 9.This construction is duplicated on the opposite side of the supportmember and by proper adjustment of the nuts 36 the weight can beadjusted to any desired position. It will be observed that the indicia49 adjacent the periphery of the support member 9 indicates any relativeangular position so that instructions may be given to the operator toset the weight at any desired angular position.

In order to adjust the weight it is only necessary to loosen the nuts 36somewhat and to either slide the weight and the strap 31circumferentially around the support member or to turn the crank shaft,so that the Weight member 3| is in its lowermost position, loosen thenuts 36 and then turn the crank shaft slightly until the weight arrivesat the desired position, whereupon the nuts can then be tightened.

The weight member 42 and the strap 43 are identical with the weight 3|and strap 31 except that they are positioned on the trackway 2|.

Particular attention is directed to the fact that the weights 3| and 42are not in the same vertical plane, that while they are parallel and areboth circumferentially adjustable they can be adjusted to eithercoincide, lead, or lag with respect to each other or with respect to thecrank pin openings 1. If it is desired to obtain a large amount ofcounterbalance at any one particular point the two weights may beadjusted to coincide with each other, which is believed to be a featureof particular advantage which has not been heretofore possible withcounterbalance devices where a plurality of weights werecircumferentially adjustable upon the same trackway.

A plurality of key-ways l3 have been provided so that the support member9 may be taken ofi' periodically and turned a portion of a revolution soas to vary the load upon the gears and to obtain a more uniform wearingof the parts.

Figs. 4 to 6 inclusive show the constructionwhich has just beendescribed as applied to a double cranking unit where as seen in Fig. 4the pumping unit is illustrated generally at I and. has the crank shaftH projecting from both sides of the gear box.

Fig. shows a construction quite similar to that described in connectionwith Fig. 3 except that a somewhat different type of counterbalance arm50 has been afiixed to the shaft II. This particular type of arm has theadjustableweights 5i which are slidable along the sides of the crank 58and to which crank the wrist pin 6 is connected. The walking beam is thesame as: shown in Fig. 3 and has beam rods 52 passing down into the well53.

The opposite end of the crank shaft I I has a. counter-balance Weightunit such as shown in. Figs. 1 and 2 connected therewith. A wrist pin.55 is connected into one of the openings I and as seen in Fig. 6 has aconnecting rod 60 arranged thereon. This connecting rod extends to aswing H which is mounted on a support 62 and is pivoted on the centeriron 63. This swing includues a beam 65 which has the converging braces66 meeting at an apex 61 to which the pull rods 68 and 69 from twospaced wells may be connected.

The particular construction of this swing is disclosed in theapplication for patent of J. L. Fincher filed August 17, 1936, SerialNo. 96,148 for Combination swing and knockout for cranking units, whilethe standard crank 50 of Fig. 5 is disclosed in the patent to Trout, No.1,588,784, granted June 15, 1926.

The construction of this modification is of particular advantage becauseat least three wells may be pumped with a single pumping unit and theuniversal adjustment of the weights 3| and 42 permit any desired amountof counterbalancing of the swing 6| regardless of whether one or morewells are connected therewith.

Broadly the invention contemplates an adjustable counterbalance weightdevice wherein the weights may be universally adjustable with respect toeach other and with respect to the wrist pin connection, and adjustmentfor a plurality of wells may be made on the counterbalance.

What is claimed is:

1. An adjustable counterbalance device for well pumping units having apitman rod comprising a body member, means to afilx said body to theshaft of the pumping unit, means to connect the pitman rod to said body,a pair of spaced grooves about the periphery of said body, acounterbalance weight member clamped in each groove for adjustment aboutthe body, said weights being independent so that they may be adjusted to:any circumferential position, and means to independently clamp eachweight to the body member.

2. A counterbalance device of the character described comprising aconcentric support member to be afiixed to a pumping unit shaft, an an-.nular groove in its periphery, a Weight, a shank on said weight to fitin said groove, a cap member to also fit in said groove, and means toclamp said cap and shank together to enclose said support member andafiix the weight for rotation with the member.

3. A counterbalance device of the character described comprising aconcentric support member to be afiixed to a pumping unit shaft, an an-:nular groove in its periphery, a Weight, a shank on said weight to fitin said groove, a cap member to also fit in said groove, and means toclamp .said cap and shank together to enclose said sup- ;port member andaffix the weight for rotation with the member, and a second groove andsecond weight and cap also on said support member, :said Weights beingindependent so that the two weights may be adjusted to lead, lag orcoincide.

ROBERT E. SCHULLER.

